Tian, Lulu
Guo, Hui
Jia, Rui
Yang, Yang
Funding for this research was provided by:
National Natural Science Foundation of China (11801569)
Natural Science Foundation of Shandong Province (ZR2018BA011)
National Natural Science Foundation of China (11571367)
Fundamental Research Funds for the Central Universities (18CX05003A)
National Science Foundation (DMS-1818467)
Article History
Received: 19 December 2019
Revised: 13 January 2020
Accepted: 18 January 2020
First Online: 10 February 2020